summaryrefslogtreecommitdiff
blob: d0a3c96e6b0595a1d04936da237edeba5531a1f4 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
763
764
765
766
767
768
769
770
771
772
773
774
775
776
777
778
779
780
781
782
783
784
785
786
787
788
789
790
791
792
793
794
795
796
797
798
799
800
801
802
803
804
805
806
807
808
809
810
811
812
813
814
815
816
817
818
819
820
821
822
823
824
825
826
827
828
829
830
831
832
833
834
835
836
837
838
839
840
841
842
843
844
845
846
847
848
849
850
851
852
853
854
855
856
857
858
859
860
861
862
863
864
865
866
867
868
869
870
871
872
873
874
875
876
877
878
879
880
881
882
883
884
885
886
887
888
889
890
891
892
893
894
895
896
897
898
899
900
901
902
903
904
905
906
907
908
909
910
911
912
913
914
915
916
917
918
919
920
921
922
923
924
925
926
927
928
929
930
931
932
933
934
935
936
937
938
939
940
941
942
943
944
945
946
947
948
949
950
951
952
953
954
955
956
957
958
959
960
961
962
963
964
965
966
967
968
969
970
971
972
973
974
975
976
977
978
979
980
981
982
983
984
985
986
987
988
989
990
991
992
993
994
995
996
997
998
999
1000
1001
1002
1003
1004
1005
1006
1007
1008
1009
1010
1011
1012
1013
1014
1015
1016
1017
1018
1019
1020
1021
# Copyright 1999-2023 Gentoo Authors
# Distributed under the terms of the GNU General Public License v2

# @ECLASS: linux-info.eclass
# @MAINTAINER:
# kernel@gentoo.org
# @AUTHOR:
# Original author: John Mylchreest <johnm@gentoo.org>
# @SUPPORTED_EAPIS: 6 7 8
# @BLURB: eclass used for accessing kernel related information
# @DESCRIPTION:
# This eclass is used as a central eclass for accessing kernel
# related information for source or binary already installed.
# It is vital for linux-mod.eclass to function correctly, and is split
# out so that any ebuild behaviour "templates" are abstracted out
# using additional eclasses.
#
# "kernel config" in this file means:
# The .config of the currently installed sources is used as the first
# preference, with a fall-back to bundled config (/proc/config.gz) if available.
#
# Before using any of the config-handling functions in this eclass, you must
# ensure that one of the following functions has been called (in order of
# preference), otherwise you will get bugs like #364041):
# linux-info_pkg_setup
# linux-info_get_any_version
# get_version
# get_running_version

case ${EAPI} in
	6|7|8) ;;
	*) die "${ECLASS}: EAPI ${EAPI:-0} not supported" ;;
esac

if [[ -z ${_LINUX_INFO_ECLASS} ]]; then
_LINUX_INFO_ECLASS=1

# A Couple of env vars are available to effect usage of this eclass
# These are as follows:


# @ECLASS_VARIABLE: CHECKCONFIG_DONOTHING
# @USER_VARIABLE
# @DEFAULT_UNSET
# @DESCRIPTION:
# Do not error out in check_extra_config if CONFIG settings are not met.
# This is a user flag and should under _no circumstances_ be set in the ebuild.
: "${CHECKCONFIG_DONOTHING:=""}"

# @ECLASS_VARIABLE: KERNEL_DIR
# @DESCRIPTION:
# A string containing the directory of the target kernel sources. The default value is
# "/usr/src/linux"
KERNEL_DIR="${KERNEL_DIR:-${ROOT%/}/usr/src/linux}"

# @ECLASS_VARIABLE: CONFIG_CHECK
# @DEFAULT_UNSET
# @DESCRIPTION:
# A string containing a list of .config options to check for before
# proceeding with the install.
#
#   e.g.: CONFIG_CHECK="MTRR"
#
# You can also check that an option doesn't exist by
# prepending it with an exclamation mark (!).
#
#   e.g.: CONFIG_CHECK="!MTRR"
#
# To simply warn about a missing option, prepend a '~'.
# It may be combined with '!'.
#
# In general, most checks should be non-fatal. The only time fatal checks should
# be used is for building kernel modules or cases that a compile will fail
# without the option.
#
# This is to allow usage of binary kernels, and minimal systems without kernel
# sources.

# @ECLASS_VARIABLE: ERROR_<CFG>
# @DEFAULT_UNSET
# @DESCRIPTION:
# A string containing the error message to display when the check against CONFIG_CHECK
# fails. <CFG> should reference the appropriate option used in CONFIG_CHECK.
#
# e.g.: ERROR_MTRR="MTRR exists in the .config but shouldn't!!"
#
# CONFIG_CHECK="CFG" with ERROR_<CFG>="Error Message" will die
# CONFIG_CHECK="~CFG" with ERROR_<CFG>="Error Message" calls eerror without dying
# CONFIG_CHECK="~CFG" with WARNING_<CFG>="Warning Message" calls ewarn without dying


# @ECLASS_VARIABLE: KBUILD_OUTPUT
# @DEFAULT_UNSET
# @DESCRIPTION:
# A string passed on commandline, or set from the kernel makefile. It contains the directory
# which is to be used as the kernel object directory.

# There are also a couple of variables which are set by this, and shouldn't be
# set by hand. These are as follows:

# @ECLASS_VARIABLE: KERNEL_MAKEFILE
# @INTERNAL
# @DESCRIPTION:
# According to upstream documentation, by default, when make looks for the makefile, it tries
# the following names, in order: GNUmakefile, makefile and Makefile. Set this variable to the
# proper Makefile name or the eclass will search in this order for it.
# See https://www.gnu.org/software/make/manual/make.html
: "${KERNEL_MAKEFILE:=""}"

# @ECLASS_VARIABLE: KV_FULL
# @OUTPUT_VARIABLE
# @DESCRIPTION:
# A read-only variable. It's a string containing the full kernel version. ie: 2.6.9-gentoo-johnm-r1

# @ECLASS_VARIABLE: KV_MAJOR
# @OUTPUT_VARIABLE
# @DESCRIPTION:
# A read-only variable. It's an integer containing the kernel major version. ie: 2

# @ECLASS_VARIABLE: KV_MINOR
# @OUTPUT_VARIABLE
# @DESCRIPTION:
# A read-only variable. It's an integer containing the kernel minor version. ie: 6

# @ECLASS_VARIABLE: KV_PATCH
# @OUTPUT_VARIABLE
# @DESCRIPTION:
# A read-only variable. It's an integer containing the kernel patch version. ie: 9

# @ECLASS_VARIABLE: KV_EXTRA
# @OUTPUT_VARIABLE
# @DESCRIPTION:
# A read-only variable. It's a string containing the kernel EXTRAVERSION. ie: -gentoo

# @ECLASS_VARIABLE: KV_LOCAL
# @OUTPUT_VARIABLE
# @DESCRIPTION:
# A read-only variable. It's a string containing the kernel LOCALVERSION concatenation. ie: -johnm

# @ECLASS_VARIABLE: KV_DIR
# @OUTPUT_VARIABLE
# @DESCRIPTION:
# A read-only variable. It's a string containing the kernel source directory, will be null if
# KERNEL_DIR is invalid.

# @ECLASS_VARIABLE: KV_OUT_DIR
# @OUTPUT_VARIABLE
# @DESCRIPTION:
# A read-only variable. It's a string containing the kernel object directory, will be KV_DIR unless
# KBUILD_OUTPUT is used. This should be used for referencing .config.

# @ECLASS_VARIABLE: SKIP_KERNEL_CHECK
# @USER_VARIABLE
# @DEFAULT_UNSET
# @DESCRIPTION:
# Do not check for kernel sources or a running kernel version.
# Main use-case is for chroots.
# This is a user flag and should under _no circumstances_ be set in the ebuild.
: "${SKIP_KERNEL_CHECK:=""}"

# And to ensure all the weirdness with crosscompile
inherit toolchain-funcs
[[ ${EAPI} == 6 ]] && inherit eapi7-ver

# bug #75034
case ${ARCH} in
	ppc)	BUILD_FIXES="${BUILD_FIXES} TOUT=${T}/.tmp_gas_check";;
	ppc64)	BUILD_FIXES="${BUILD_FIXES} TOUT=${T}/.tmp_gas_check";;
esac

# @FUNCTION: set_arch_to_kernel
# @DESCRIPTION:
# Set the env ARCH to match what the kernel expects.
set_arch_to_kernel() { export ARCH=$(tc-arch-kernel); }

# @FUNCTION: set_arch_to_pkgmgr
# @DESCRIPTION:
# Set the env ARCH to match what the package manager expects.
set_arch_to_pkgmgr() { export ARCH=$(tc-arch); }

# @FUNCTION: qout
# @DESCRIPTION:
# qout <einfo | ewarn | eerror> is a quiet call when EBUILD_PHASE should not have visible output.
qout() {
	local outputmsg type
	type=${1}
	shift
	outputmsg="${@}"
	case "${EBUILD_PHASE}" in
		depend)  unset outputmsg;;
		clean)   unset outputmsg;;
		preinst) unset outputmsg;;
	esac
	[[ -n "${outputmsg}" ]] && ${type} "${outputmsg}"
}

# @FUNCTION: qeinfo
# @DESCRIPTION:
# qeinfo is a quiet einfo call when EBUILD_PHASE should not have visible output.
qeinfo() { qout einfo "${@}" ; }

# @FUNCTION: qewarn
# @DESCRIPTION:
# qewarn is a quiet ewarn call when EBUILD_PHASE should not have visible output.
qewarn() { qout ewarn "${@}" ; }

# @FUNCTION: qeerror
# @DESCRIPTION:
# qeerror is a quiet error call when EBUILD_PHASE should not have visible output.
qeerror() { qout eerror "${@}" ; }

# File Functions
# ---------------------------------------

# @FUNCTION: getfilevar
# @USAGE: <variable> <configfile>
# @RETURN: the value of the variable
# @DESCRIPTION:
# It detects the value of the variable defined in the file 'configfile'. This is
# done by including the 'configfile', and printing the variable with Make.
# It WILL break if your makefile has missing dependencies!
getfilevar() {
	local ERROR basefname basedname myARCH="${ARCH}"
	ERROR=0

	[[ -z "${1}" ]] && ERROR=1
	[[ ! -f "${2}" ]] && ERROR=1

	if [[ "${ERROR}" = 1 ]]; then
		echo -e "\n"
		eerror "getfilevar requires 2 variables, with the second a valid file."
		eerror "   getfilevar <VARIABLE> <CONFIGFILE>"
	else
		basefname="$(basename ${2})"
		basedname="$(dirname ${2})"
		unset ARCH

		# We use nonfatal because we want the caller to take care of things #373151
		# Pass need-config= to make to avoid config check in kernel Makefile.
		# Pass dot-config=0 to avoid the config check in kernels prior to 5.4.
		echo -e "e:\\n\\t@echo \$(${1})\\ninclude ${basefname}" | \
			nonfatal emake -C "${basedname}" --no-print-directory M="${T}" \
			dot-config=0 need-config= need-compiler= \
			${BUILD_FIXES} -s -f - 2>/dev/null

		ARCH=${myARCH}
	fi
}

# @FUNCTION: getfilevar_noexec
# @USAGE: <variable> <configfile>
# @RETURN: the value of the variable
# @DESCRIPTION:
# It detects the value of the variable defined in the file 'configfile'.
# This is done with sed matching an expression only. If the variable is defined,
# you will run into problems. See getfilevar for those cases.
getfilevar_noexec() {
	local ERROR basefname basedname mycat myARCH="${ARCH}"
	ERROR=0
	mycat='cat'

	[[ -z "${1}" ]] && ERROR=1
	[[ ! -f "${2}" ]] && ERROR=1
	[[ "${2%.gz}" != "${2}" ]] && mycat='zcat'

	if [[ "${ERROR}" = 1 ]]; then
		echo -e "\n"
		eerror "getfilevar_noexec requires 2 variables, with the second a valid file."
		eerror "   getfilevar_noexec <VARIABLE> <CONFIGFILE>"
	else
		${mycat} "${2}" | \
		sed -n \
		-e "/^[[:space:]]*${1}[[:space:]]*:\\?=[[:space:]]*\(.*\)\$/{
			s,^[^=]*[[:space:]]*=[[:space:]]*,,g ;
			s,[[:space:]]*\$,,g ;
			p
		}"
	fi
}

# @ECLASS_VARIABLE: _LINUX_CONFIG_EXISTS_DONE
# @INTERNAL
# @DESCRIPTION:
# This is only set if one of the linux_config_*exists functions has been called.
# We use it for a QA warning that the check for a config has not been performed,
# as linux_chkconfig* in non-legacy mode WILL return an undefined value if no
# config is available at all.
_LINUX_CONFIG_EXISTS_DONE=

# @FUNCTION: linux_config_qa_check
# @INTERNAL
# @DESCRIPTION:
# Helper function which returns an error before the function argument is run if no config exists
linux_config_qa_check() {
	local f="$1"

	if [[ -z "${_LINUX_CONFIG_EXISTS_DONE}" ]]; then
		ewarn "QA: You called $f before any linux_config_exists!"
		ewarn "QA: The return value of $f will NOT guaranteed later!"
	fi

	if ! use kernel_linux; then
		die "$f called on non-Linux system, please fix the ebuild"
	fi
}

# @FUNCTION: linux_config_src_exists
# @RETURN: true or false
# @DESCRIPTION:
# It returns true if .config exists in a build directory otherwise false
linux_config_src_exists() {
	export _LINUX_CONFIG_EXISTS_DONE=1
	use kernel_linux && [[ -n ${KV_OUT_DIR} && -s ${KV_OUT_DIR}/.config ]]
}

# @FUNCTION: linux_config_bin_exists
# @RETURN: true or false
# @DESCRIPTION:
# It returns true if .config exists in /proc, otherwise false
linux_config_bin_exists() {
	export _LINUX_CONFIG_EXISTS_DONE=1
	use kernel_linux && [[ -s /proc/config.gz ]]
}

# @FUNCTION: linux_config_exists
# @RETURN: true or false
# @DESCRIPTION:
# It returns true if .config exists otherwise false
#
# This function MUST be checked before using any of the linux_chkconfig_*
# functions.
linux_config_exists() {
	linux_config_src_exists || linux_config_bin_exists
}

# @FUNCTION: linux_config_path
# @DESCRIPTION:
# Echo the name of the config file to use.  If none are found,
# then return false.
linux_config_path() {
	if linux_config_src_exists; then
		echo "${KV_OUT_DIR}/.config"
	elif linux_config_bin_exists; then
		echo "/proc/config.gz"
	else
		return 1
	fi
}

# @FUNCTION: require_configured_kernel
# @DESCRIPTION:
# This function verifies that the current kernel is configured (it checks against the existence of .config)
# otherwise it dies.
require_configured_kernel() {
	[[ -n ${SKIP_KERNEL_CHECK} ]] && return

	if ! use kernel_linux; then
		die "${FUNCNAME}() called on non-Linux system, please fix the ebuild"
	fi

	if ! linux_config_src_exists; then
		qeerror "Could not find a usable .config in the kernel source directory."
		qeerror "Please ensure that ${KERNEL_DIR} points to a configured set of Linux sources."
		qeerror "If you are using KBUILD_OUTPUT, please set the environment var so that"
		qeerror "it points to the necessary object directory so that it might find .config."
		die "Kernel not configured; no .config found in ${KV_OUT_DIR}"
	fi

	get_version || die "Unable to determine configured kernel version"
}

# @FUNCTION: linux_chkconfig_present
# @USAGE: <option>
# @RETURN: true or false
# @DESCRIPTION:
# It checks that CONFIG_<option>=y or CONFIG_<option>=m is present in the current kernel .config
# If linux_config_exists returns false, the results of this are UNDEFINED. You
# MUST call linux_config_exists first.
linux_chkconfig_present() {
	[[ -n ${SKIP_KERNEL_CHECK} ]] && return
	linux_config_qa_check linux_chkconfig_present
	[[ $(getfilevar_noexec "CONFIG_$1" "$(linux_config_path)") == [my] ]]
}

# @FUNCTION: linux_chkconfig_module
# @USAGE: <option>
# @RETURN: true or false
# @DESCRIPTION:
# It checks that CONFIG_<option>=m is present in the current kernel .config
# If linux_config_exists returns false, the results of this are UNDEFINED. You
# MUST call linux_config_exists first.
linux_chkconfig_module() {
	[[ -n ${SKIP_KERNEL_CHECK} ]] && return
	linux_config_qa_check linux_chkconfig_module
	[[ $(getfilevar_noexec "CONFIG_$1" "$(linux_config_path)") == m ]]
}

# @FUNCTION: linux_chkconfig_builtin
# @USAGE: <option>
# @RETURN: true or false
# @DESCRIPTION:
# It checks that CONFIG_<option>=y is present in the current kernel .config
# If linux_config_exists returns false, the results of this are UNDEFINED. You
# MUST call linux_config_exists first.
linux_chkconfig_builtin() {
	[[ -n ${SKIP_KERNEL_CHECK} ]] && return
	linux_config_qa_check linux_chkconfig_builtin
	[[ $(getfilevar_noexec "CONFIG_$1" "$(linux_config_path)") == y ]]
}

# @FUNCTION: linux_chkconfig_string
# @USAGE: <option>
# @RETURN: CONFIG_<option>
# @DESCRIPTION:
# It prints the CONFIG_<option> value of the current kernel .config (it requires a configured kernel).
# If linux_config_exists returns false, the results of this are UNDEFINED. You
# MUST call linux_config_exists first.
linux_chkconfig_string() {
	[[ -n ${SKIP_KERNEL_CHECK} ]] && return
	linux_config_qa_check linux_chkconfig_string
	getfilevar_noexec "CONFIG_$1" "$(linux_config_path)"
}

# Versioning Functions
# ---------------------------------------

# @FUNCTION: kernel_is
# @USAGE: [-lt -gt -le -ge -eq] <major_number> [minor_number patch_number]
# @RETURN: true or false
# @DESCRIPTION:
# It returns true when the current kernel version satisfies the comparison against the passed version.
# -eq is the default comparison.
#
# @CODE
# For Example where KV = 2.6.9
# kernel_is 2 4   returns false
# kernel_is 2     returns true
# kernel_is 2 6   returns true
# kernel_is 2 6 8 returns false
# kernel_is 2 6 9 returns true
# @CODE

# Note: duplicated in kernel-2.eclass
kernel_is() {
	if ! use kernel_linux; then
		die "${FUNCNAME}() called on non-Linux system, please fix the ebuild"
	fi

	# If we haven't determined the version yet, we need to.
	linux-info_get_any_version

	# Now we can continue
	local operator

	case ${1#-} in
	  lt) operator="-lt"; shift;;
	  gt) operator="-gt"; shift;;
	  le) operator="-le"; shift;;
	  ge) operator="-ge"; shift;;
	  eq) operator="-eq"; shift;;
	   *) operator="-eq";;
	esac
	[[ $# -gt 3 ]] && die "Error in ${ECLASS}_${FUNCNAME}(): too many parameters"

	ver_test \
		"${KV_MAJOR:-0}.${KV_MINOR:-0}.${KV_PATCH:-0}" \
		"${operator}" \
		"${1:-${KV_MAJOR:-0}}.${2:-${KV_MINOR:-0}}.${3:-${KV_PATCH:-0}}"
}

# @FUNCTION: get_makefile_extract_function
# @INTERNAL
# @DESCRIPTION:
# Check if the Makefile is valid for direct parsing.
# Check status results:
# - PASS, use 'getfilevar' to extract values
# - FAIL, use 'getfilevar_noexec' to extract values
# The check may fail if:
# - make is not present
# - corruption exists in the kernel makefile
get_makefile_extract_function() {
	[[ -n ${SKIP_KERNEL_CHECK} ]] && return
	local a='' b='' mkfunc='getfilevar'
	a="$(getfilevar VERSION ${KERNEL_MAKEFILE})"
	b="$(getfilevar_noexec VERSION ${KERNEL_MAKEFILE})"
	[[ "${a}" != "${b}" ]] && mkfunc='getfilevar_noexec'
	echo "${mkfunc}"
}

# @ECLASS_VARIABLE: get_version_warning_done
# @INTERNAL
# @DESCRIPTION:
# Internal variable, so we know to only print the warning once.
get_version_warning_done=

# @FUNCTION: get_version
# @DESCRIPTION:
# It gets the version of the kernel inside KERNEL_DIR and populates the KV_FULL variable
# (if KV_FULL is already set it does nothing).
#
# The kernel version variables (KV_MAJOR, KV_MINOR, KV_PATCH, KV_EXTRA and KV_LOCAL) are also set.
#
# The KV_DIR is set using the KERNEL_DIR env var, the KV_OUT_DIR is set using a valid
# KBUILD_OUTPUT (in a decreasing priority list, we look for the env var, makefile var or the
# symlink /lib/modules/${KV_MAJOR}.${KV_MINOR}.${KV_PATCH}${KV_EXTRA}/build).
get_version() {
	if ! use kernel_linux; then
		die "${FUNCNAME}() called on non-Linux system, please fix the ebuild"
	fi

	local tmplocal

	[[ -n ${SKIP_KERNEL_CHECK} ]] && return

	# No need to execute this twice assuming KV_FULL is populated.
	# We can force by unsetting KV_FULL.
	[[ -n "${KV_FULL}" ]] && return 0

	# If we don't know KV_FULL, then we need to.
	# Make sure KV_DIR isn't set since we need to work it out via KERNEL_DIR.
	unset KV_DIR

	# KV_DIR will contain the full path to the sources directory we should use
	[[ -z "${get_version_warning_done}" ]] && \
	qeinfo "Determining the location of the kernel source code"
	[[ -d "${KERNEL_DIR}" ]] && KV_DIR="${KERNEL_DIR}"

	if [[ -z "${KV_DIR}" ]]; then
		if [[ -z "${get_version_warning_done}" ]]; then
			get_version_warning_done=1
			qewarn "Unable to find kernel sources at ${KERNEL_DIR}"
			#qeinfo "This package requires Linux sources."
			if [[ "${KERNEL_DIR}" == "/usr/src/linux" ]] ; then
				qeinfo "Please make sure that ${KERNEL_DIR} points at your running kernel, "
				qeinfo "(or the kernel you wish to build against)."
				qeinfo "Alternatively, set the KERNEL_DIR environment variable to the kernel sources location"
			else
				qeinfo "Please ensure that the KERNEL_DIR environment variable points at full Linux sources of the kernel you wish to compile against."
			fi
		fi
		return 1
	fi

	# See if the kernel dir is actually an output dir. #454294
	if [[ -z "${KBUILD_OUTPUT}" && -L "${KERNEL_DIR}/source" ]]; then
		KBUILD_OUTPUT=${KERNEL_DIR}
		KERNEL_DIR=$(readlink -f "${KERNEL_DIR}/source")
		KV_DIR=${KERNEL_DIR}
	fi

	if [[ -z "${get_version_warning_done}" ]]; then
		qeinfo "Found kernel source directory:"
		qeinfo "    ${KV_DIR}"
	fi

	kernel_get_makefile

	if [[ ! -s ${KERNEL_MAKEFILE} ]]; then
		if [[ -z "${get_version_warning_done}" ]]; then
			get_version_warning_done=1
			qeerror "Could not find a Makefile in the kernel source directory."
			qeerror "Please ensure that ${KERNEL_DIR} points to a complete set of Linux sources"
		fi
		return 1
	fi

	# OK so now we know our sources directory, but they might be using
	# KBUILD_OUTPUT, and we need this for .config and localversions-*
	# so we better find it, eh?
	#
	# Do we pass KBUILD_OUTPUT on the CLI?
	local OUTPUT_DIR=${KBUILD_OUTPUT}

	if [[ -z ${OUTPUT_DIR} ]]; then
		# Decide the function used to extract makefile variables.
		local mkfunc=$(get_makefile_extract_function "${KERNEL_MAKEFILE}")

		# And if we didn't pass it, we can take a nosey in the Makefile.
		OUTPUT_DIR=$(${mkfunc} KBUILD_OUTPUT "${KERNEL_MAKEFILE}")
	fi

	# And contrary to existing functions, I feel we shouldn't trust the
	# directory name to find version information as this seems insane.
	# So we parse ${KERNEL_MAKEFILE}.
	KV_MAJOR=$(getfilevar VERSION "${KERNEL_MAKEFILE}")
	KV_MINOR=$(getfilevar PATCHLEVEL "${KERNEL_MAKEFILE}")
	KV_PATCH=$(getfilevar SUBLEVEL "${KERNEL_MAKEFILE}")
	KV_EXTRA=$(getfilevar EXTRAVERSION "${KERNEL_MAKEFILE}")

	if [[ -z "${KV_MAJOR}" || -z "${KV_MINOR}" || -z "${KV_PATCH}" ]]; then
		if [[ -z "${get_version_warning_done}" ]]; then
			get_version_warning_done=1
			qeerror "Could not detect kernel version."
			qeerror "Please ensure that ${KERNEL_DIR} points to a complete set of Linux sources."
		fi
		return 1
	fi

	[[ -d "${OUTPUT_DIR}" ]] && KV_OUT_DIR="${OUTPUT_DIR}"
	if [[ -n "${KV_OUT_DIR}" ]]; then
		qeinfo "Found kernel object directory:"
		qeinfo "    ${KV_OUT_DIR}"
	fi
	# and if we STILL have not got it, then we better just set it to KV_DIR
	KV_OUT_DIR="${KV_OUT_DIR:-${KV_DIR}}"

	# Grab the kernel release from the output directory.
	# TODO: we MUST detect kernel.release being out of date, and 'return 1' from
	# this function.
	if [[ -s "${KV_OUT_DIR}"/include/config/kernel.release ]]; then
		KV_LOCAL=$(<"${KV_OUT_DIR}"/include/config/kernel.release)
	elif [[ -s "${KV_OUT_DIR}"/.kernelrelease ]]; then
		KV_LOCAL=$(<"${KV_OUT_DIR}"/.kernelrelease)
	else
		KV_LOCAL=
	fi

	# KV_LOCAL currently contains the full release; discard the first bits.
	tmplocal=${KV_LOCAL#${KV_MAJOR}.${KV_MINOR}.${KV_PATCH}${KV_EXTRA}}

	# If the updated local version was not changed, the tree is not prepared.
	# Clear out KV_LOCAL in that case.
	# TODO: this does not detect a change in the localversion part between
	# kernel.release and the value that would be generated.
	if [[ "${KV_LOCAL}" = "${tmplocal}" ]]; then
		KV_LOCAL=
	else
		KV_LOCAL=${tmplocal}
	fi

	# and in newer versions, we can also pull LOCALVERSION if it is set.
	# but before we do this, we need to find if we use a different object directory.
	# This *WILL* break if the user is using localversions, but we assume it was
	# caught before this if they are.
	if [[ -z ${OUTPUT_DIR} ]] ; then
		# Try to locate a kernel that is most relevant for us.
		for OUTPUT_DIR in "${SYSROOT}" "${ROOT%/}" "" ; do
			OUTPUT_DIR+="/lib/modules/${KV_MAJOR}.${KV_MINOR}.${KV_PATCH}${KV_EXTRA}${KV_LOCAL}/build"
			if [[ -e ${OUTPUT_DIR} ]] ; then
				break
			fi
		done
	fi

	# And we should set KV_FULL to the full expanded version
	KV_FULL="${KV_MAJOR}.${KV_MINOR}.${KV_PATCH}${KV_EXTRA}${KV_LOCAL}"

	qeinfo "Found sources for kernel version:"
	qeinfo "    ${KV_FULL}"

	return 0
}

# @FUNCTION: get_running_version
# @DESCRIPTION:
# It gets the version of the current running kernel and the result is the same as get_version() if the
# function can find the sources.
get_running_version() {
	if ! use kernel_linux; then
		die "${FUNCNAME}() called on non-Linux system, please fix the ebuild"
	fi

	local kv=$(uname -r)

	if [[ -f ${ROOT%/}/lib/modules/${kv}/source/Makefile ]]; then
		KERNEL_DIR=$(readlink -f "${ROOT%/}/lib/modules/${kv}/source")
		if [[ -f ${ROOT%/}/lib/modules/${kv}/build/Makefile ]]; then
			KBUILD_OUTPUT=$(readlink -f "${ROOT%/}/lib/modules/${kv}/build")
		fi
		get_version && return 0
	fi

	KV_FULL=${kv}

	# This handles a variety of weird kernel versions.  Make sure to update
	# tests/linux-info_get_running_version.sh if you want to change this.
	local kv_full=${KV_FULL//[-+_]*}
	KV_MAJOR=$(ver_cut 1 ${kv_full})
	KV_MINOR=$(ver_cut 2 ${kv_full})
	KV_PATCH=$(ver_cut 3 ${kv_full})
	KV_EXTRA="${KV_FULL#${KV_MAJOR}.${KV_MINOR}${KV_PATCH:+.${KV_PATCH}}}"
	: "${KV_PATCH:=0}"

	return 0
}

# This next function is named with the eclass prefix to avoid conflicts with
# some old versionator-like eclass functions.

# @FUNCTION: linux-info_get_any_version
# @DESCRIPTION:
# This attempts to find the version of the sources, and otherwise falls back to
# the version of the running kernel.
linux-info_get_any_version() {
	if ! use kernel_linux; then
		die "${FUNCNAME}() called on non-Linux system, please fix the ebuild"
	fi

	if ! get_version; then
		ewarn "Unable to calculate Linux Kernel version for build, attempting to use running version"
		if ! get_running_version; then
			die "Unable to determine any Linux Kernel version, please report a bug"
		fi
	fi
}


# ebuild check functions
# ---------------------------------------

# @FUNCTION: check_kernel_built
# @DESCRIPTION:
# This function verifies that the current kernel sources have been already prepared otherwise it dies.
check_kernel_built() {
	if ! use kernel_linux; then
		die "${FUNCNAME}() called on non-Linux system, please fix the ebuild"
	fi

	# If we haven't determined the version yet, we need to

	[[ -n ${SKIP_KERNEL_CHECK} ]] && return

	require_configured_kernel

	local versionh_path
	if kernel_is -ge 3 7; then
		versionh_path="include/generated/uapi/linux/version.h"
	else
		versionh_path="include/linux/version.h"
	fi

	if [[ ! -f "${KV_OUT_DIR}/${versionh_path}" ]]; then
		eerror "These sources have not yet been prepared."
		eerror "We cannot build against an unprepared tree."
		eerror "To resolve this, please type the following:"
		eerror
		eerror "# cd ${KV_DIR}"
		eerror "# make oldconfig"
		eerror "# make modules_prepare"
		eerror
		eerror "Then please try merging this module again."
		die "Kernel sources need compiling first"
	fi
}

# @FUNCTION: check_modules_supported
# @DESCRIPTION:
# This function verifies that the current kernel support modules (it checks CONFIG_MODULES=y) otherwise it dies.
check_modules_supported() {
	if ! use kernel_linux; then
		die "${FUNCNAME}() called on non-Linux system, please fix the ebuild"
	fi

	# If we haven't determined the version yet, we need to.
	require_configured_kernel

	if ! linux_chkconfig_builtin "MODULES"; then
		eerror "These sources do not support loading external modules."
		eerror "to be able to use this module please enable \"Loadable modules support\""
		eerror "in your kernel, recompile and then try merging this module again."
		die "No support for external modules in ${KV_FULL} config"
	fi
}

# @FUNCTION: check_extra_config
# @DESCRIPTION:
# It checks the kernel config options specified by CONFIG_CHECK. It dies only when a required config option (i.e.
# the prefix ~ is not used) doesn't satisfy the directive. Ignored on non-Linux systems.
check_extra_config() {
	use kernel_linux || return

	local config negate die error reworkmodulenames
	local soft_errors_count=0 hard_errors_count=0 config_required=0
	# Store the value of the QA check, because otherwise we won't catch usages
	# after if check_extra_config is called AND other direct calls are done
	# later.
	local old_LINUX_CONFIG_EXISTS_DONE="${_LINUX_CONFIG_EXISTS_DONE}"

	# If we haven't determined the version yet, we need to.
	linux-info_get_any_version

	# Determine if we really need a .config. The only time when we don't need
	# one is when all of the CONFIG_CHECK options are prefixed with "~".
	for config in ${CONFIG_CHECK}; do
		if [[ "${config:0:1}" != "~" ]]; then
			config_required=1
			break
		fi
	done

	if [[ ${config_required} == 0 ]]; then
		# In the case where we don't require a .config, we can now bail out
		# if the user has no .config as there is nothing to do. Otherwise
		# code later will cause a failure due to missing .config.
		if ! linux_config_exists; then
			ewarn "Unable to check for the following kernel config options due"
			ewarn "to absence of any configured kernel sources or compiled"
			ewarn "config:"
			for config in ${CONFIG_CHECK}; do
				config=${config#\~}
				config=${config#\!}
				local_error="ERROR_${config}"
				msg="${!local_error}"
				if [[ -z ${msg} ]]; then
					local_error="WARNING_${config}"
					msg="${!local_error}"
				fi
				ewarn " - ${config}${msg:+ - }${msg}"
			done
			ewarn "You're on your own to make sure they are set if needed."
			export LINUX_CONFIG_EXISTS_DONE="${old_LINUX_CONFIG_EXISTS_DONE}"
			return 0
		fi
	elif ! linux_config_exists; then
		qeerror "Could not find a neither a usable .config in the kernel source directory"
		qeerror "nor a /proc/config.gz file,"
		qeerror "Please ensure that ${KERNEL_DIR} points to a configured set of Linux sources."
		qeerror "If you are using KBUILD_OUTPUT, please set the environment var so that"
		qeerror "it points to the necessary object directory so that it might find .config"
		qeerror "or have a properly configured kernel to produce a config.gz file. (CONFIG_IKCONFIG)."
		die "Kernel not configured; no .config found in ${KV_OUT_DIR} or /proc/config.gz found"
	fi

	ebegin "Checking for suitable kernel configuration options"

	for config in ${CONFIG_CHECK}; do
		# If we specify any fatal, ensure we honor them
		die=1
		error=0
		negate=0
		reworkmodulenames=0

		if [[ ${config:0:1} == "~" ]]; then
			die=0
			config=${config:1}
		elif [[ ${config:0:1} == "@" ]]; then
			die=0
			reworkmodulenames=1
			config=${config:1}
		fi
		if [[ ${config:0:1} == "!" ]]; then
			negate=1
			config=${config:1}
		fi

		if [[ ${negate} == 1 ]]; then
			linux_chkconfig_present ${config} && error=2
		elif [[ ${reworkmodulenames} == 1 ]]; then
			local temp_config="${config//*:}" i n
			config="${config//:*}"
			if linux_chkconfig_present ${config}; then
				for i in ${MODULE_NAMES}; do
					n="${i//${temp_config}}"
					[[ -z ${n//\(*} ]] && \
						MODULE_IGNORE="${MODULE_IGNORE} ${temp_config}"
				done
				error=2
			fi
		else
			linux_chkconfig_present ${config} || error=1
		fi

		if [[ ${error} -gt 0 ]]; then
			local report_func="eerror" local_error
			local_error="ERROR_${config}"
			local_error="${!local_error}"

			if [[ -z "${local_error}" ]]; then
				# using old, deprecated format.
				local_error="${config}_ERROR"
				local_error="${!local_error}"
			fi
			if [[ ${die} == 0 && -z "${local_error}" ]]; then
				#soft errors can be warnings
				local_error="WARNING_${config}"
				local_error="${!local_error}"
				if [[ -n "${local_error}" ]] ; then
					report_func="ewarn"
				fi
			fi

			if [[ -z "${local_error}" ]]; then
				[[ ${error} == 1 ]] \
					&& local_error="is not set when it should be." \
					|| local_error="should not be set. But it is."
				local_error="CONFIG_${config}:\t ${local_error}"
			fi
			if [[ ${die} == 0 ]]; then
				${report_func} "  ${local_error}"
				soft_errors_count=$[soft_errors_count + 1]
			else
				${report_func} "  ${local_error}"
				hard_errors_count=$[hard_errors_count + 1]
			fi
		fi
	done

	if [[ ${hard_errors_count} -gt 0 ]]; then
		eend 1
		eerror "Please check to make sure these options are set correctly."
		eerror "Failure to do so may cause unexpected problems."
		eerror "Once you have satisfied these options, please try merging"
		eerror "this package again."
		export LINUX_CONFIG_EXISTS_DONE="${old_LINUX_CONFIG_EXISTS_DONE}"
		die "Incorrect kernel configuration options"
	elif [[ ${soft_errors_count} -gt 0 ]]; then
		eend 1
		ewarn "Please check to make sure these options are set correctly."
		ewarn "Failure to do so may cause unexpected problems."
	else
		eend 0
	fi
	export LINUX_CONFIG_EXISTS_DONE="${old_LINUX_CONFIG_EXISTS_DONE}"
}

# @FUNCTION: check_zlibinflate
# @DESCRIPTION:
# Function to make sure a ZLIB_INFLATE configuration has the required symbols.
check_zlibinflate() {
	if ! use kernel_linux; then
		die "${FUNCNAME}() called on non-Linux system, please fix the ebuild"
	fi

	# If we haven't determined the version yet, we need to.
	require_configured_kernel

	# although I restructured this code - I really really really dont support it!

	# bug #27882 - zlib routines are only linked into the kernel
	# if something compiled into the kernel calls them
	#
	# plus, for the cloop module, it appears that there's no way
	# to get cloop.o to include a static zlib if CONFIG_MODVERSIONS
	# is on

	local INFLATE
	local DEFLATE

	einfo "Determining the usability of ZLIB_INFLATE support in your kernel"

	ebegin "checking ZLIB_INFLATE"
	linux_chkconfig_builtin CONFIG_ZLIB_INFLATE
	eend $? || die

	ebegin "checking ZLIB_DEFLATE"
	linux_chkconfig_builtin CONFIG_ZLIB_DEFLATE
	eend $? || die

	local LINENO_START
	local LINENO_END
	local SYMBOLS
	local x

	LINENO_END="$(grep -n 'CONFIG_ZLIB_INFLATE y' ${KV_DIR}/lib/Config.in | cut -d : -f 1)"
	LINENO_START="$(head -n $LINENO_END ${KV_DIR}/lib/Config.in | grep -n 'if \[' | tail -n 1 | cut -d : -f 1)"
	(( LINENO_AMOUNT = ${LINENO_END} - ${LINENO_START} ))
	(( LINENO_END = ${LINENO_END} - 1 ))
	SYMBOLS="$(head -n $LINENO_END ${KV_DIR}/lib/Config.in | tail -n $LINENO_AMOUNT | sed -e 's/^.*\(CONFIG_[^\" ]*\).*/\1/g;')"

	# okay, now we have a list of symbols
	# we need to check each one in turn, to see whether it is set or not
	for x in ${SYMBOLS} ; do
		if [[ "${!x}" = "y" ]]; then
			# We have a winner!
			einfo "${x} ensures zlib is linked into your kernel - excellent"
			return 0
		fi
	done

	eerror
	eerror "This kernel module requires ZLIB library support."
	eerror "You have enabled zlib support in your kernel, but haven't enabled"
	eerror "enabled any option that will ensure that zlib is linked into your"
	eerror "kernel."
	eerror
	eerror "Please ensure that you enable at least one of these options:"
	eerror

	for x in ${SYMBOLS} ; do
		eerror "  * $x"
	done

	eerror
	eerror "Please remember to recompile and install your kernel, and reboot"
	eerror "into your new kernel before attempting to load this kernel module."

	die "Kernel doesn't include zlib support"
}

################################
# Default pkg_setup
# Also used when inheriting linux-mod to force a get_version call
# @FUNCTION: linux-info_pkg_setup
# @DESCRIPTION:
# Force a get_version() call when inherited from linux-mod.eclass and then check if the kernel is configured
# to support the options specified in CONFIG_CHECK (if not null)
linux-info_pkg_setup() {
	use kernel_linux || return

	linux-info_get_any_version

	[[ -n "${CONFIG_CHECK}" && -z ${CHECKCONFIG_DONOTHING} ]] && check_extra_config
}

# @FUNCTION: kernel_get_makefile
# @DESCRIPTION:
# Support the possibility that the Makefile could be one of the following and should
# be checked in the order described here:
# https://www.gnu.org/software/make/manual/make.html
# Order of checking and valid Makefiles names:  GNUMakefile, makefile, Makefile
kernel_get_makefile() {

	[[ -s ${KV_DIR}/GNUMakefile ]] && KERNEL_MAKEFILE="${KV_DIR}/GNUMakefile" && return
	[[ -s ${KV_DIR}/makefile ]] && KERNEL_MAKEFILE="${KV_DIR}/makefile" && return
	[[ -s ${KV_DIR}/Makefile ]] && KERNEL_MAKEFILE="${KV_DIR}/Makefile" && return

}

fi

EXPORT_FUNCTIONS pkg_setup